The easiest way I know to explain and understand identity is this way: a person’s identity is his or her own sense of self; of who they are. For example, your identity may be that you are a female, who is honest, warm, caring, intelligent, and sometimes moody. This then might be your identity, and you carry it with you wherever you go. The way you perceive yourself, your actions, your thoughts, and your interactions with others are all influenced by this identity.
For example, if you do something very well (like getting an “A” on an exam), you might associated it with your identity – “of course I got an ‘A’, I am an intelligent person who does well on things I set my mind to.” Likewise, when we do something wrong, bad, or simply goes against our identity, we may protect ourselves by attributing this behaviour to something or someone else (I failed the test because the teacher gave all trick questions, not because I am not intelligent).